We report on experimental realizations of full-Stokes polarization perfect absorption based on all-metal diatomic metasurfaces in the mid-infrared (mid IR) regime. The exploited physical mechanism is based on the combination of near field coupling effects and abrupt phase shift effects. These metasurfaces exhibit distinguished absorption response for a pair of orthogonal polarization states—linear, circular, or elliptical. This is in contrast to previous perfect absorbers which could only address orthogonal linear, and to a limited extent, circular polarizations. Our results significantly expand the scope of metamaterials-based perfect absorbers, offering a new methodology to implement novel photonic devices to many applications, i.e., thermal imaging, molecular fingerprint detection, and quantum computing.